Megan Allen has replaced Harry Williams as director of the Thomas Crane Public Library. Allen, who has worked for Quincy libraries since 1986, was sworn in to the position last week to take over for Williams, who retired recently due to health reasons. The library’s Board of Trustees had recommended Allen to Mayor Thomas Koch for the position in a meeting on Feb. 11. “Megan has been a longtime valuable member of the library team,” said mayoral spokesman Christopher Walker. “She was a finalist in the appointment process through the board in the last round when Harry was appointed.” In a letter to the board, Allen said she welcomed the opportunity to work with all segments of the city “to sustain and strengthen the Thomas Crane Library’s vital role in the community.”